What would a dentist do about teeth discoloration?

I know the obvious answer is whitening treatments, but read on.

My boyfriend hasn’t been to the dentist since probably 2007. When we met he had pretty, white, straight teeth. However, he dips and isn’t very good about flossing or brushing at night. So now his bottom teeth and back teeth are fine, but his four front teeth have some discoloration. Nothing really bad, but I think he may have a cavity or two on the front teeth. He has dental insurance, but I hear dental insurance companies don’t pay for much outside of yearly cleanings.

He’s making an appointment for x-rays, cleaning, and a check up to see what the doctor can do for him, but I want to get an idea beforehand. I know none of you can really answer, but maybe you have an idea of what could be done and about how much it might cost.

Would crowns most likely be used? I hear they are $1500 for each tooth. That’s a lot of money. Do a lot of dentists do payment plans? Could fillings be done and a whitening treatment or do they not normally do fillings on front teeth?